REFLECTING SCHOOLS
If two mirrors are turned face-to-face, each will reflect the other’s reflection of itself, and so on. Thus is generated (at least in theory) an image that resembles a tunnel going on forever—albeit to nowhere in particular. In practice, of course, there are limits to just how far this regress reaches. The mirrors have to be absolutely parallel, and any distortions on their surfaces ruin the effect. But even a glimpse of this virtual abyss can be sublime. Either that or queasy-making.